Bumping gaia.json for 2 gaia-central revision(s)

========

https://hg.mozilla.org/integration/gaia-central/rev/204d793347d1
Author: Dominic Kuo <dkuo@mozilla.com>
Desc: Merge pull request #10500 from dominickuo/bug-884722

Bug 884722 - [music] support amr for open activity, r=timdream

========

https://hg.mozilla.org/integration/gaia-central/rev/d14a7daf171c
Author: Dominic Kuo <dkuo@mozilla.com>
Desc: Bug 884722 - [music] support amr for open activity

b2g/config/gaia.json

@@ -1,4 +1,4 @@
 {
-    "revision": "4b7a20107e22b409251823a83bcf7ae6d771b89d", 
+    "revision": "204d793347d1633dca71db4cf2909bf9377018bc", 
     "repo_path": "/integration/gaia-central"
 }